ON the matter of bicycling under the influence, Michael Dolan has known both pleasure and pain.

Mr. Dolan, a 33-year-old public relations strategist, reported some happy two-wheeled encounters while drunk involving the singers David Byrne and Björk — whom he witnessed “being pedaled around and screeching like a child” — as well as a “surreal” collision with a rider on a Penny Farthing.

But he also acknowledged the danger in trying to ride after downing enough alcohol to make a single speed look like a tandem. “I know one person who was killed drunk-biking, one who broke some bones crossing the Manhattan Bridge,” Mr. Dolan said. “Everyone I ride with has at least one story of hurting themselves booze-rolling.” (Mr. Byrne, for one, wrote on his blog about having broken his ribs in a drink-fueled 2008 fall.)

Still, many cyclists have dedicated “bar bikes” — cheap beaters that can be left overnight if a return trip by taxi becomes necessary — and sometimes there are so many bikes locked up near certain watering holes that it can be hard to find a place to park.

The city’s health department conducted blood-alcohol tests on the bodies of 176 of the 225 cyclists killed in accidents between 1996 and 2005. Of the 84 tests considered valid — some were done too late — 18 cyclists were found to have drunk before their crashes, according to the study, released last year, though it was unclear how much.

Not that it matters how much: biking under the influence is not explicitly illegal in New York, though a drunk cyclist can be charged with reckless endangerment or public intoxication, just as a pedestrian can.

The landmark case in local B.U.I. law, such as it is, did not actually involve a bicycle. In 1970, the police arrested Bernard Szymanski for piloting a horse-drawn carriage while drunk. A judge dismissed the case, noting, with some chagrin, that the statutes applied only to “motor vehicles,” and not those under horse — or human — power, like bicycles.

Some places around the country, though, treat all vehicles equally. In Oregon, for example, both biking and driving under the influence can result in a lost driver’s license, according to Bob Mionske, author of the 2007 book “Bicycling and the Law.” (Not that you need a driver’s license to get back on the bike.) An appeals court decision this year appears to put Washington, D.C., in the same category.

But in South Dakota, lawmakers in 2007 excluded bicycles, tricycles and any other “unpowered foot-pedal conveyance” from the drunken-driving statutes, arguing that this might help intoxicated people find safer ways home. And in Utah, people can be arrested for bicycling under the influence, but the punishment is generally lighter than for those driving a car.

Jimmy Carbone, a bicycle lover who owns the East Village bar Jimmy’s No. 43, said he discovered something of a stigma against drinking and riding when trying to organize a barhopping (bar-pedaling?) night among several spots in Manhattan and northwest Brooklyn last summer.

“After we put it out there, biking groups didn’t want to be associated with it,” Mr. Carbone said. He insisted the idea was not to drink to excess — “Why would we get hammered if we’re riding our bikes?” — but to create a kind of “European sensibility.” Nevertheless, the promotion was not repeated this year.

“Biking in New York is scary enough” sober, said Kimberly Burgas, a 26-year-old Web designer who lives in Williamsburg. “Biking while drunk, now that’s a serious game of Frogger. I’m not willing to play.”

But Cathy Erway, a 28-year-old writer, admitted to tipsy pedaling. “If I was too drunk to walk straight, I wouldn’t,” she said. “Then again, if I know I have my bike outside I wouldn’t drink that much to begin with.”

In the state of Indiana, a person can be arrested for DUI for operating any wheeled vehicle while intoxicated, with a single exception for wheelchairs.

This is the way it should be in all states. A person who is intoxicated while operating a bicycle, especially at night, is more likely to operate the bicycle in a manner that is dangerous to himself and other riders. If a drunk cyclist suddenly swerves out into traffic, for example, a nearby driver might lose control of his vehicle attempting to miss the cyclist, resulting in an automobile crash. Furthermore, the cyclist could crash into another cyclist or into a pedestrian, resulting in some pretty severe injuries for the hapless victim. Drunk people have no business being on the road, except as passengers.

I had a friend in high school whose car was run over by a drunken bicyclist. He drove an Alfa Romeo Spider, and was stopped at a traffic signal. The bike hit the car head-on, and the front wheel made it well onto the hood before the drunken man fell to the ground.